1. Field of the Invention
The present invention relates to an electric junction box provided with a plurality of relays.
2. Description of Related Art
A conventionally known electric junction box mounted in a vehicle is disposed between a battery and vehicle electrical components, such as a lamp and a horn, and is provided with a plurality of relays that connect or disconnect power to the vehicle electrical components.
With a recent increase in vehicle electrical components, the number of relays mounted in the electric junction box also tends to increase. In addition, the electric junction box is required to be smaller. Compared with other electrical components, such as a fuse, a relay is a large component. In particular, the size of a high-voltage relay is substantially large, thus requiring a large mounting space. It is thus required that a conductive circuit be disposed efficiently in terms of space, the conductive circuit including a space for mounting a relay and a bus bar. In order to conduct power to coil power supply terminals of a plurality of relays, in particular, it is necessary to wire a conductive circuit of a bus bar from a coil power supply portion, such as a connector housing for conducting power to coils, to the coil power supply terminals of the relays. It is important to dispose the bus bar for conduction efficiently in terms of space to the coil power supply terminals of the relays.
Japanese Patent Laid-open Publication No. 2005-130634 discloses a configuration to improve space efficiency in which relays are mounted alternately in opposite directions so as to secure an area to dispose bus bars and the bus bars for the relays are partitioned by insulating plates and disposed in layer.
However, the configuration of Japanese Patent Laid-open Publication No. 2005-130634, which requires the bus bars to be partitioned by the insulating plates and layered, incurs cost increase due to an increase in the number of components and falls short of meeting the demand of downsizing due to the height of the electric junction box. Furthermore, a connector mounting portion for conduction, which is a power supply portion, is provided separately away from a relay mounting portion. Thus, a distance to a coil power supply terminal is long and a circumstance in which a large space is required to place the bus bars is not sufficiently addressed.